Microelectronic circuits are typically fabricated on single-crystal silicon substrates. Fabrication of such circuits requires that several different materials, deposited or grown as thin films, contact the silicon substrate in precise patterns. For example, a field effect transistor formed on a silicon substrate requires an insulating gate dielectric thin film overlying the channel region of the transistor, and may also require a film forming several conductive contacts to the substrate on opposite sides of this channel region.
The microelectronics industry continually strives to increase performance, decrease power consumption, and decrease per-unit costs of microelectronic circuits. To realize these goals, each new generation of circuits typically integrates smaller devices onto the silicon substrate than its predecessors did, including in many cases thinner films contacting the silicon substrate. Miniaturization of devices is now approaching the level where the quality of the interface between the substrate and a deposited film, on an atomic scale, becomes significant.